Pump Dispenser

Abstract

It is an object of the present invention to provide a pump dispenser having a ventilation hole at a position higher than a packing seal plane in order to prevent leakage and, at the same time, to cause the pump dispenser to be also advantageous in terms of cost by simplifying the mold structure as much as possible. The pump dispenser having a cap 1 attached to an opening portion of a container main body 13 containing a liquid has: a housing 2 having a body portion 2 a engaged with the cap, a cylinder 3 fit in the housing and disposed above a seal portion, and a piston member 6 slidable in the cylinder; wherein a ventilation hole 3 b 1 is formed in the cylinder, and a ventilation channel communicated with outside air P for releasing a negative pressure in the container main body is formed between the outer wall of the cylinder and the inner wall of the housing. The cylinder 3 is fit in the housing so that the cylinder is supported by a rib 2 d formed on the inner wall of the housing 2.

1 . A pump dispenser having a cap attached to an opening portion of a container main body containing a liquid, the pump dispenser comprising: 
 a housing having a body portion engaged with the cap;    a cylinder fit in the housing and disposed above a seal portion; and    a piston member slidable in the cylinder; wherein    a ventilation hole is formed in the cylinder, and a ventilation channel communicated with outside air for releasing a negative pressure in the container main body is formed between an outer wall of the cylinder and an inner wall of the housing.    
   
   
       2 . The pump dispenser described in  claim 1 , wherein a first fold portion and a second fold portion below the first fold portion for sealing the interior of the cylinder are formed in the piston member.  
   
   
       3 . The pump dispenser described in  claim 2 , wherein the ventilation hole of the cylinder is positioned above the first fold portion in the state in which the interior of the container main body and the outside air are mutually communicated.  
   
   
       4 . The pump dispenser described in  claim 2 , wherein the ventilation hole of the cylinder is positioned between the first fold portion and the second fold portion in the state before the liquid in the container main body is jetted.  
   
   
       5 . The pump dispenser described in  claim 1 , wherein a large-diameter portion of the piston member is welded on the housing with pressure so as to block the ventilation channel.  
   
   
       6 . The pump dispenser described in  claim 1 , wherein the cylinder is fit in the housing so that the cylinder is supported by a rib formed on the inner wall of the housing.  
   
   
       7 . The pump dispenser described in  claim 1 , wherein an annular handle portion is formed in the housing for facilitating holding of the pump dispenser.